Data processing system having a resume function and an operating method thereof

ABSTRACT

A data processing method and apparatus have a resume function and use a password. When a power switch of a data processing system is turned on while it is selected that the resume function is to be enabled and the password is to be collated, the data processing system displays a message prompting an operator to input a password. When a predetermined password is input from a keyboard or the like, the data processing system executes resume processing, i.e., executes data processing to be continued to data processing executed immediately before the power switch was turned off. When the predetermined password is not input, the resume operation is inhibited, and a content saved by the resume function can be prevented from being disclosed to or destroyed by a third party.

This application is a Continuation of application Ser. No. 08/040,995,filed on Mar. 31, 1993, now abandoned, which is a continuation ofapplication Ser. No. 07/507,490, filed on Apr. 11, 1990, U.S. Pat. No.5,222,231.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a computer having a resume function,i.e., a function of executing data processing, after the main powerswitch is turned back on, according to data processing state which hadbeen in operation immediately before a main power switch was turned off.

2. Description of the Related Art

A computer having a resume function is known. The resume function is afunction of resuming a job (data processing and/or display) which was inoperation immediately before a main power switch was turned off when themain power switch is turned on.

The resume function is realized as follows. An ON/OFF (enable/disable)state of the resume function is set in a setup mode (installation mode).When the main power switch is turned off while the resume function isenabled, necessary data in memories, registers, and pointers are savedin a backup memory. When the main power switch is turned on again, thesaved data are restored to their original locations. Thereafter, the job(data processing) continues according to the restored content.

In a conventional computer, when the resume function is enabled, even ifa third party who has no right to use the computer turns on the mainpower switch of the computer, the contents of the data processing systemimmediately before the power switch was turned off is restored. For thisreason, in a conventional computer having the resume function, the datasaved by the resume function may be destroyed by a third party, thusposing a problem of data protection. Since a display in use when thepower switch was turned off is displayed by the resume function when thepower switch is turned on, the data may be presented to a third party.

SUMMARY OF THE INVENTION

The present invention has been made in consideration of the abovesituation, and has as its object to provide an improved computer and adata processing method.

It is another object of the present invention to provide a computer anda data processing method, which can prevent the contents saved by aresume function from being destroyed by a third party or being disclosedto the third party.

In order to achieve the above object, a data processing system having aresume function of the present invention comprises:

switch means (11) for turning on and off a main power source of the dataprocessing system;

OFF detection means (9, 4) for detecting that the switch means (11) isturned off;

backup memory means (2), responsive to the detection result of the OFFdetection means (4, 9), for holding a content of data processingexecuted by the data processing means (1-8, 12) immediately before theswitch means (11) is turned off;

ON detection means (4, 9) for detecting that the switch means (11) isturned on;

identification data holding means (2) for holding identification datafor specifying an operator;

input means (6, 8) for inputting the identification data for specifyingan operator;

discrimination means (4), responsive to the ON detection means (4, 9),for discriminating whether or not identification data input from theinput means (6, 8) after the switch means (11) is turned on coincideswith identification data stored in the holding means (2); and

means (2, 4) for, when the discrimination means (4) detects acoincidence, executing data processing, from processing executedimmediately before the switch means (11) is turned off, in accordancewith a storage content of the backup memory means (2).

In order to achieve the above object, a data processing method of thepresent invention comprises the steps of:

processing data;

turning off a power switch;

holding a content of data processing executed in the data processingstep in response to OFF of the power switch;

turning on the power switch again;

inputting identification data for specifying an operator after the powerswitch is turned on;

collating the input identification data and prestored identificationdata; and

executing data processing, to be continued to data processing executedbefore the power switch is turned off, in accordance with the contentsheld in the holding step when a coincidence between the twoidentification data is detected in the collating step.

As described above, according to the computer and the data processingmethod of the present invention, even if a power switch of a dataprocessing system is turned on, resume processing is inhibited until thecorrect identification data is input. For this reason, the contentssaved by the resume function can be prevented from being disclosed to ordestroyed by a third party.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the invention and may of the attendantadvantages thereof will be readily obtained as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings, wherein:

FIG. 1 is a block diagram showing an arrangement of a computer accordingto the first embodiment of the present invention;

FIG. 2 is a flow chart showing an operation in a setup mode of thecomputer shown in FIG. 1;

FIG. 3 is a flow chart showing an operation when a power switch of thecomputer shown in FIG. 1 is turned on;

FIG. 4 is a flow chart showing an operation when the power switch of thecomputer shown in FIG. 1 is turned off; and

FIG. 5 is a flow chart showing a modification of the flow chart shown inFIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings, wherein like reference numerals designateidentical or corresponding parts throughout the several views, and moreparticularly to FIG. 1 thereof.

FIG. 1 is a block diagram of a computer having a resume function.

The computer shown in FIG. 1 comprises a BIOS ROM (Basic Input OutputSystem Read Only Memory) 1; a backup RAM 2; a system memory (mainmemory) 3; a CPU (Central Processing Unit) 4; a display controller 5; akeyboard controller 6; a display 7; a keyboard 8; a power controller 9;a power circuit 10; a power switch 11; and a system bus 12.

The BIOS ROM 1 stores a BIOS (Basic Input Output System), and a setupprogram PA (to be described later).

The backup RAM 2 comprises a volatile memory supplied with a backuppower VBK or an EEPROM. The backup RAM 2 saves the contents of a systemmemory, registers in the CPU, control registers, hardware registers, aninstruction pointer, and the like when the main power switch is turnedoff while the resume function is enabled. The backup RAM 2 includes apassword area for storing a password, a check sum, and a password flag(to be described later). Normally, access to this password area isinhibited.

The system memory 3 as the main memory stores a setup program PB, data,programs, and the like. The difference between the setup programs PB andPA will be described later. The system memory 3 is used upon executionof the setup program, and is also used as a data area for the BIOS ROM1.

The CPU 4 is the core of the arrangement of FIG. 1, and is operated inaccordance with the programs stored in the system memory 3 to executedata processing.

The display controller 5 controls the operation of the display. Thedisplay 7 comprises, e.g., a liquid crystal display, a plasma display, aCRT, or the like. The display 7 displays characters, images, and thelike under the control of the display controller 5.

The keyboard controller 6 detects an operation of a key at the keyboard8, and informs the content of the key operation to the CPU 4.

The power controller 9 includes, e.g., an exclusive power control CPUfor controlling power supply. When the power switch 11 is ON, the powercontroller 9 outputs an operation voltage VD; when the power switch isOFF, it outputs a backup voltage VBK. Although not shown, when aplurality of types of operation voltages and backup voltages arerequired, the power controller 9 generates required voltages.

The power circuit 10 includes, e.g., a battery, a backup battery, an ACadapter circuit, a charger, and the like, and supplies a power to thepower controller 9.

The system bus 12 includes a data bus, an address bus, a control bus,and the like, and is connected to the BIOS ROM 1, the backup RAM 2, theCPU 4, the display controller 5, the keyboard controller 6, and thepower controller 9 to transfer data, addresses, control signals to them.

The setup program PA stored in the BIOS ROM 1 is a program forperforming various setups (e.g., ON/OFF of the resume function), andchanging setup values. For example, the setup program PA includes aroutine for setting an ON/OFF state of the resume function, a routinefor setting a password, an IRT (Initial Reliability Test), a controlroutine of various I/O devices, and the like. The setup program PA isstarted upon operation of a specific key or keys on the keyboard 8.

The setup program PB performs setup of an ON/OFF state of the resumefunction, and setup of a password together with the setup program PA. Inaddition, the setup program PB sets up hardware components. Theoperations of the setup program PB are different from those of the setupprogram PA except for setup of an ON/OFF state of the resume function,and setup of a password. The setup program exists as an external commandof the computer.

The operation of the computer shown in FIG. 1 will be described belowwith reference to FIGS. 2 through 4.

The characteristic feature of the operation of the computer shown inFIG. 1 will be briefly described. When the power is turned on (i.e.,when the power switch 11 is turned on), if the resume function isenabled, the computer shown in FIG. 1 causes the display 7 to display amessage to prompt input of a password. When an operator inputs a correctpassword, the resume function is executed, and data processing anddisplay are resumed from a state which execute immediately before thepower switch 11 was turned off. On the other hand, when the power switch11 is turned on, if the resume function is disabled, this computerinitializes its hardware components in the same manner as in a computerwithout the resume function, and then executes data processing.

An operation of setting an ON/OFF state of the resume function of thecomputer with the arrangement shown in FIG. 1 will be described belowwith reference to FIG. 2.

After the power switch 11 is turned on, an operator depresses apredetermined key on the keyboard 8 to start the setup program PA oroperates the keyboard 8 to input a command for starting the setupprogram PB. The keyboard controller 6 detects the key operation, andsupplies a key operation signal to the CPU 4. In response to the keyoperation signal, the CPU 4 starts one of the setup programs PA and PB(step S1). The setup program includes various other contents, asdescribed above, and their processing is executed if necessary (stepS2). When processing of the setup program reaches a stage of setting anON/OFF state of the resume function, the CPU 4 controls the displaycontroller 5 to cause the display 7 to display a frame for inquiringwhether or not the resume function is to be enabled (step S3). Theinquiry frame may be a menu for inquiring whether or not the resumefunction is to be enabled. In response to this inquiry, an operatorinputs an answer indicating whether the resume function is to be enabledor disabled at the keyboard 8. The input content is checked in step S4.

If the input contents indicates that the resume function is to bedisabled, the CPU 4 sets a resume disable flag indicating OFF of theresume function (or resets a resume enable flag) at a predeterminedposition of the backup RAM 2 (step S5). Thereafter, the flow advances toother processing.

If the input content indicates that the resume function is to beenabled, the flow advances to step S6. In step S6, the CPU 4 sets theresume enable flag indicating ON of the resume function at thepredetermined position of the backup RAM 2. The CPU 4 controls thedisplay controller 5 to cause the display 7 to display a frame forinquiring whether or not a password is to be set (step S7). This inquiryframe may be a menu for inquiring whether or not a password is to beset. In response to the inquiry on the screen, an operator inputs ananswer indicating whether or not a password is to be set at the keyboard8. The input content is checked in step S8.

If the input content does not indicate that a password is to be set, aflag indicating this is set at a predetermined position of the backupRAM 2 (or resets a password flag) (step S9). Thereafter, the flowadvances to other processing.

If the input content indicates that a password is to be set, the flowadvances to step S10. In step S10, the CPU 4 sets the password flagindicating that a password is to be set at the predetermined position ofthe backup RAM 2. When setup of a password is selected, an operatorinputs a password from the keyboard 8. The CPU 4 causes the display 7 todisplay the input password. When the displayed password is correct, theoperator depresses an enter key. In response to this, input of thepassword is detected in step S11. A check sum corresponding to the inputpassword is calculated (step S12). The input password and the check sumare stored in the backup RAM 2 together with the password flag (stepS13). The password is saved in the backup RAM 2 in the form of ASCIIcodes. Thereafter, the flow advances to other processing. After thesetup operation, normal data processing is continued.

When one or a plurality of passwords are set in advance in the computerto restrict users of the computer, it is checked to see if the inputpassword coincides with one of these passwords. Only when a coincidenceis found, the input password may be set in the backup RAM 2.

An operation when the power switch 11 is turned on will be describedbelow.

When the power switch 11 is turned on, the power controller 9 detectsit. The power controller 9 supplies the operation voltage VD. The powercontroller 9 outputs an NMI signal indicating power ON to the CPU 4. Inresponse to the NMI signal, the CPU 4 executes the operation shown inFIG. 3.

The CPU 4 checks to see if the resume enable flag is set in the RAM 2(step S21). If no resume enable flag is set in the backup RAM 2, sincethe resume operation need not be executed, the CPU 4 executes normalhardware initialization (step S22). Thereafter, the flow advances tonormal data processing (step S23). If the resume enable flag is set inthe RAM 2, it is checked to see if the password flag is set (step S24).

If the password flag is not set, the CPU 4 restores the contents savedin the backup RAM 2 upon previous power OFF to the original locations(step S25). For example, the saved contents of the CPU registers, thesystem memory 3, the hardware registers, and the instruction pointer arerestored to the CPU registers, the system memory 3, the hardwareregisters, and the instruction pointer. Thereafter, the flow advances tonormal data processing (step S23).

If it is determined in step S24 that the password flag is set, the checksum stored in the backup RAM 2 is checked, and it is also checked if thecontent of the backup RAM 2 is not destroyed (step S26). If an error isdetected as a result of checking, an error message is displayed on thedisplay 7 (step S27), and hardware initialization is executed (stepS22). Thereafter, the flow advances to normal data processing (stepS23).

If it is determined in step S26 that the check result is OK (no error),a message to urge the operator to input a password is displayed on thedisplay 7 (step S28). When the operator inputs a password according tothis display, it is checked to see if the input password coincides withthe prestored password (stored in the backup RAM 2 in step S13). If acoincidence is found between the two passwords, steps S25 and S23described above are executed. On the other hand, if a noncoincidence isfound between the input password and the prestored password, the flowreturns to step S28 to urge the operator to reinput the password.

When the above-mentioned processing sequence is adopted, a state of dataprocessing and a display state immediately before the power switch wasturned off are resumed only when a correct password is input. That is,resume processing is executed. In other words, execution of resumeprocessing is inhibited until the correct password is input.

More specifically, even when the resume function is enabled, the flowforms an endless loop unless a predetermined password is input, and thecontent of the backup RAM 2 is not restored in the registers, and thelike. In addition, the content of the backup RAM 2 can be prevented frombeing destroyed. Even when the power switch 11 is turned off during theendless loop, if the power switch 11 is turned on again, processing isexecuted from step S21 in FIG. 3. Therefore, the content of the RAM 2can be protected.

An operation of the CPU 4 when the power switch 11 is turned off will bedescribed below with reference to FIG. 4.

When the power controller 9 detects that the power switch 11 is turnedoff, it sends a signal indicating this, e.g., the NMI signal to the CPU4. In response to the NMI signal, the CPU 4 executes the processingshown in FIG. 4. The CPU 4 first checks if the resume enable flag is setin the backup RAM 2 (step S41). If the resume enable flag is not set,the CPU 4 controls the power controller 9 to stop output of theoperation voltage VD and to output the backup voltage VBK (step S42).

When the resume enable flag is set, the CPU 4 saves the contents of theregisters in the CPU 4, the system memory 3, the control registers, thehardware registers, and the instruction pointer (pointer indicating aposition of a program in execution when the power switch 11 is turnedoff) to the backup RAM 2. As described above, the saved contents arerestored from the backup RAM 2 to original locations when the powerswitch 11 is turned on again. Thereafter, the CPU 4 controls the powercontroller 9 to stop the output of the operation voltage VD and tooutput the backup voltage VBK (step S42).

The backup voltage VBK is kept as the output until the power switch 11is turned on and the operation voltage VD is generated. Thus, thecontents saved in the backup RAM are held. When the backup voltage VBKis also supplied to the system memory 3, the content of the systemmemory 3 need not be saved to the backup RAM 2.

As described above, according to this embodiment, even when the resumefunction is enabled, the system cannot be resumed to a state immediatelybefore the power switch was turned off unless a correct password isinput. For this reason, data saved by the resume function can beprevented from being destroyed or disclosed to a third party.

The present invention is not limited to the above embodiment. In theabove embodiment, two types of setup programs are used. However, asingle setup program may be used.

A password is used to check whether or not an operator is a legal user.In a computer comprising another personal identification data, e.g., IDcard reader, an ID card may be used in place of a password.

If the setup program PA or PB is ready to start when the power switch 11is turned on, the resume function may be switched to be OFF or setup ofa password may be switched to OFF. In order to avoid this, as shown inFIG. 5, step S31 of disabling execution of the setup program may beinserted before step S21, and step S32 of enabling execution of thesetup program may be inserted before step S23. Alternatively, executionof the setup program may be disabled in a loop constituted by steps S28,S29, and S30.

Obviously, numerous (additional) modifications and variations of thepresent invention are possible in light of the above teachings. It istherefore to be understood that within the scope of the appended claims,the invention may be practiced otherwise than as specifically describedherein.

What is claimed is:
 1. A data processing system having a resume functionand a security managing function, comprising:switch means for switchingon and off a main power of said data processing system; switch detectionmeans, coupled to said switch means, for detecting that said switchmeans has switched on or off said main power; memory means, coupled tosaid switch detection means, and responsive to a detection result ofsaid switch detection means, for storing contents of data processingimmediately before the main power is turned off; holding means forholding identification data; input means for inputting identificationdata for security management; discriminating means, coupled to saidswitch detection means, said holding means, and said input means, saiddiscriminating means being responsive to said switch detection means,for discriminating whether identification data input from said inputmeans after said switch means has switched on said main power coincideswith identification data held in said holding means; executing meansfor, in response to detection of a coincidence by said discriminatingmeans, executing data processing, from processing executed immediatelybefore the main power was switched off, in accordance with a storagecontent of said memory means; and means for inhibiting a resumption ofthe data processing, to prevent contents of the data processing frombeing revealed to an unauthorized person, in response to detection of anon-coincidence by said discriminating means.
 2. The data processingsystem according to claim 1, further comprising:selection means forselection of when identification data is to be collated, said selectionmeans enabling discrimination by said discriminating means in responseto the selection; and allowing means, coupled to said holding means, forallowing setting of the identification data in said holding means. 3.The data processing system according to claim 1, furthercomprising:second selection means for selecting enabling/disabling ofthe resume function; and third selection means for selecting when tocollate identification data, wherein said discriminating means isoperated when said second selection means selects enabling of the resumefunction and said third selection means selects collation of theidentification data.
 4. The data processing system according to claim 3,further comprising:means for setting a first flag indicating ON/OFF ofthe resume function; and means for setting a second flag indicating whenidentification data is to be collated, wherein said discriminating meansis operated when the first flag is set to indicate that the resumefunction is enabled and the second flag is set to indicate that theidentification data is to be collated.
 5. An operating method of asystem which has a resume function and a security management system andwhich can run a plurality of programs comprising prestoringidentification data, wherein said system comprises:a data processor forprocessing data; a power switch having ON and OFF states for switchingthe data processing system ON and OFF; holding means for holdingcontents of data processing performed by said data processor in responseto an OFF state of said power switch; inputting means for inputtingidentification data for security management; and collating means forcollating identification data input by said inputting means andprestored identification data to ensure system security; wherein saidoperating method comprises the steps of:processing data by means of saiddata processor; switching off the power switch; holding the contents ofthe data held in said holding means and stopping the data processingwhen the power switch is turned OFF; then switching on said powerswitch; inputting identification data via the inputting means after saidstep of turning on said power switch; collating the input identificationdata and prestored identification data; resuming data processing from adata processing condition that existed when said power switch was turnedoff in accordance with the contents of the data held in the holdingmeans during the holding step when a coincidence between the inputidentification data and prestored identification data is detected by thecollating means during the collating step; and inhibiting a resumptionof data processing immediately before the main power is turned off sothat data processing does not automatically resume when the power issubsequently turned on, to prevent contents of the data processing frombeing revealed to an unauthorized person, when non-coincidence betweenthe input identification data and the prestored identification data isdetected.
 6. The operating method according to claim 5, wherein saidsystem further comprises:first selecting means for selecting an ON/OFFstate of a resume function; and second selecting means for selectingwhen identification data is to be collated.
 7. The operating methodaccording to claim 6, further comprising the steps of:discriminatingwhen the ON state of the resume function is selected; and discriminatingwhen collation of identification data is selected, wherein the collationsteps are executed when said discriminating steps indicate that theresume function is ON and collation of the identification data isselected.
 8. The operating method according to claim 6, wherein saiddata processing system further comprises:means for displaying a messageinquiring whether or not the resume function is to be enabled; and meansfor displaying a message inquiring whether or not identification data isto be collated in a setup mode.
 9. A data processing system having aresume function and a security managing function, comprising:switchmeans for switching on and off a main power of said data processingsystem; switch detection means, coupled to said switch means, fordetecting that said switch means is switched on or off; memory means,coupled to said switch detection means, and responsive to a detectionresult of said switch detection means, for storing contents of dataprocessing immediately before the main power is turned off; holdingmeans for holding identification data; input means for inputtingidentification data for security management; discriminating means,coupled to said switch detection means, said holding means, and saidinput means, said discriminating means being responsive to said switchdetection means, for discriminating whether identification data inputfrom said input means after said switch means switches on said mainpower coincides with identification data held in said holding means;executing means for, in response to detection of a coincidence by saiddiscriminating means, executing data processing from processing executedimmediately before the main power was switched off in accordance with astorage content of said memory means; and means for inhibiting aresumption of the data processing, to prevent an unauthorized personfrom resuming the data processing.
 10. A data processing system having aresume function and a security managing function, comprising:switchmeans for switching on and off a main power of said data processingsystem; switch detection means, coupled to said switch means, fordetecting that said switch means is turned on or off; memory means,coupled to said switch detection means and responsive to a detectionresult of said switch detection means, for storing contents of dataprocessing immediately before the main power is turned off; holdingmeans for holding identification data; input means for inputtingidentification data for security management; discriminating means,coupled to said switch detection means, said holding means, and saidinput means, said discriminating means being responsive to said switchdetection means, for discriminating whether identification data inputfrom said input means after said switch means switches on said mainpower coincides with identification data held in said holding means;executing means for, in response to detection of a coincidence by saiddiscriminating means, executing data processing from processing executedimmediately before the main power was switched off, in accordance with astorage content of said memory means; and means for inhibiting aresumption of the data processing for security management, in responseto detection of a non-coincidence in said discriminating means.
 11. Adata processing system having a resume function and a security managingfunction, comprising:switch means for switching to on and off states, amain power of said data processing system; switch detection means,coupled to said switch means, for detecting that said switch means isswitching the main power to the on state or to the off state; memorymeans, coupled to said switch detection means and responsive to adetection result of said switch detection means, for storing contents ofdata processing immediately before the main power is turned off; holdingmeans for holding identification data; input means for inputtingidentification data for security management; discriminating means,coupled to said switch detection means, said holding means, and saidinput means, said discriminating means being responsive to said switchdetection means, for discriminating whether identification data inputfrom said input means after said switch means has switched on said mainpower coincides with identification data held in said holding means;executing means for, in response to detection of a coincidence by saiddiscriminating means, executing data processing, from processingexecuted immediately before the main power was switched off, inaccordance with a storage content of said memory means; and means forinhibiting a resumption of the data processing in response to detectionof a non-coincidence in said discriminating means.
 12. A data processingsystem having a resume function and a security managing function,comprising:switch means for switching on and off a main power of saiddata processing system; switch detection means, coupled to said switchmeans, for detecting that said switch means is turned on or off; memorymeans, coupled to said switch detection means, and responsive to adetection result of said switch detection means, for storing contents ofdata processing immediately before the main power is turned off; holdingmeans for holding identification data; input means for inputtingidentification data for security management; discriminating means,coupled to said switch detection means, said holding means, and saidinput means, said discriminating means being responsive to said switchdetection means, for discriminating whether identification data inputfrom said input means after said switch means switches on said mainpower coincides with identification data held in said holding means;executing means for, in response to detection of a coincidence by saiddiscriminating means, executing data processing, from processingexecuted immediately before the main power was switched off, inaccordance with a storage content of said memory means, and means forinhibiting a resumption of the data processing, in response to detectionof a non-coincidence in said discriminating means, to prevent anunauthorized person from performing the data processing.
 13. A dataprocessing system having a resume function and a security managingfunction, comprising:switch means having power on and power off states,for switching to an on and an off state, a main power of said dataprocessing system; switch detection means, coupled to said switch means,for detecting that said switch means is switched to its power on or itspower off state; memory means, coupled to said switch detection means,and responsive to a detection result of said switch detection means, forstoring contents of data processing immediately before the main power isturned off; holding means for holding identification data; input meansfor inputting identification data for security management;discriminating means coupled to said switch detection means, saidholding means, and said input means, said discriminating means beingresponsive to said switch detection means, for discriminating whetheridentification data input from said input means after said switch meansturns on said main power coincides with identification data held in saidholding means; executing means for, in response to detection of acoincidence by said discriminating means, executing data processing,from processing executed immediately before the main power was switchedoff, in accordance with a storage content of said memory means, andmeans for inhibiting a resumption of the data processing, in response todetection of a non-coincidence in said discriminating means, to preventan unauthorized person from interrupting the data processing.
 14. A dataprocessing system having a resume function and a security managingfunction, comprising:switch means, having an on state and an off state,for switching a main power of said data processing system on and off;switch detection means, coupled to said switch means, for detecting thestate of said switch means; memory means, coupled to said switchdetection means, and responsive to a detection result of said switchdetection means, for storing contents of data processing immediatelybefore the main power is switched off; holding means for holdingidentification data; input means for inputting identification data forsecurity management; discriminating means, coupled to said switchdetection means, said holding means, and said input means, saiddiscriminating means being responsive to said switch detection means,for discriminating whether identification data input from said inputmeans after said switch means turns on said main power coincides withidentification data held in said holding means; executing means for, inresponse to detection of a coincidence by said discriminating means,executing data processing from processing executed immediately beforethe main power was switched off, in accordance with a storage content ofsaid memory means, and means for inhibiting a resumption of the dataprocessing in response to detection of a non-coincidence in saiddiscriminating means, to prevent an unauthorized person from performingdata processing with the data processing system.
 15. A data processingsystem having a resume function and a security management system,comprising:first indicating means for indicating saving of contents ofdata processing performed by said data processing system; saving means,responsive to said first indicating means, for saving the contents ofthe data processing when said first indicating means indicates thesaving of the contents of the data processing; storing means for storingidentification data for security management; input means for inputtingidentification data for security management; second indicating means forindicating resuming the data processing; discriminating means coupled tosaid second indicating means, said storing means, and said input means,said discriminating means being responsive to said second indicatingmeans, for discriminating whether identification data input from saidinput means coincides with identification data stored in said storingmeans; executing means for, in response to detection of a coincidence insaid discriminating means, executing resumption of the data processingin accordance with the contents saved by said saving means, and meansfor inhibiting a resumption of data processing for security management,in response to detection of a non-coincidence in said discriminatingmeans.
 16. A data processing system having a resume function and asecurity management system, comprising:first indicating means forindicating saving of contents of data processing performed by said dataprocessing system; saving means, responsive to said first indicatingmeans, for saving the contents of the data processing when said firstindicating means indicates the saving of the contents of the dataprocessing; storing means for storing identification data for securitymanagement; input means for inputting identification data for securitymanagement; second indicating means for indicating resuming the dataprocessing; discriminating means coupled to said second indicatingmeans, said storing means, and said input means, said discriminatingmeans responsive to said second indicating means, for discriminatingwhether identification data input from said input means coincides withidentification data stored in said storing means; executing means for,in response to detection of a coincidence by said discriminating means,executing resumption of the data processing in accordance with thecontents saved by said saving means, and means for inhibiting aresumption of data processing in response to detection of anon-coincidence by said discriminating means.
 17. A data processingsystem having a resume function and a security management system,comprising:first indicating means for indicating saving of contents ofdata processing performed by said data processing system; saving means,responsive to said first indicating means, for saving the contents ofthe data processing when said first indicating means indicates thesaving of the contents of the data processing; storing means for storingidentification data for security management; input means for inputtingidentification data for security management; second indicating means forindicating resuming the data processing; discriminating means coupled tosaid second indicating means, said storing means, and said input means,said discriminating means being responsive to said second indicatingmeans, for discriminating whether identification data input from saidinput means coincides with identification data stored in said storingmeans; executing means for, in response to detection of a coincidence insaid discriminating means, executing resumption of the data processingin accordance with the contents saved by said saving means, and meansfor inhibiting a resumption of data processing, to prevent anunauthorized person from performing the data processing in response todetection of a non-coincidence by said discriminating means.
 18. A dataprocessing system having a resume function and a security managementsystem, comprising:first indicating means for indicating saving ofcontents of data processing performed by said data processing system;saving means, responsive to said first indicating means, for saving thecontents of the data processing when said first indicating meansindicates the saving of the contents of the data processing; storingmeans for storing identification data for security management; inputmeans for inputting identification data for security management; secondindicating means for indicating resuming of the data processing;discriminating means coupled to said second indicating means, saidstoring means, and said input means, said discriminating means beingresponsive to said second indicating means, for discriminating whetheridentification data input from said input means coincides withidentification data stored in said storing means; executing means for,in response to detection of a coincidence by said discriminating means,executing resumption of the data processing in accordance with thecontents saved by said saving means, and means for inhibiting aresumption of data processing, to prevent an unauthorized person frominterrupting the data processing in response to detection of anon-coincidence in said discriminating means.
 19. A data processingsystem having a resume function and a security management system,comprising:first indicating means for indicating saving of contents ofdata processing performed by said data processing system; saving means,responsive to said first indicating means, for saving the contents ofthe data processing when said first indicating means indicates thesaving of the contents of the data processing; storing means for storingidentification data for security management; input means for inputtingidentification data for security management; second indicating means forindicating resuming the data processing; discriminating means coupled tosaid second indicating means, said storing means, and said input means,said discriminating means being responsive to said second indicatingmeans, for discriminating whether identification data input from saidinput means coincides with identification data stored in said storingmeans; executing means for, in response to detection of a coincidence insaid discriminating means, executing resumption of the data processingin accordance with the contents saved by said saving means, and meansfor inhibiting a resumption of data processing, to prevent anunauthorized person from performing data processing on said dataprocessing system, in response to detection of a non-coincidence in saiddiscriminating means.
 20. An operating method of a system which has aresume function and a security management system and which can run aplurality of programs, comprising prestoring identification data,wherein said system comprises:a data processor for processing data;first indicating means for indicating saving of contents of dataprocessing performed by said data processor; holding means, responsiveto said first indicating means, for holding contents of the dataprocessing performed by said data processor when the first indicatingmeans indicates the saving of the contents of the data processingperformed by said data processor; identification data storing means forstoring identification data for security management; second indicatingmeans for indicating resuming of the data processing; inputting meansfor inputting identification data for security management; collatingmeans for collating identification data input by said inputting meansand the identification data stored in said identification data storingmeans; wherein said operating method comprises the steps of:processingdata by means of the data processor; indicating saving of the contentsof the data processing by means of said first indicating means; holdingthe contents of the data processing in said holding means and stoppingthe data processing; indicating resuming of the data processing by meansof said second indicating means; inputting identification data by meansof inputting means after said second indicating means indicates theresuming; collating the input identification data and prestoredidentification data; resuming the data processing in accordance with acontent held in the holding means, when a coincidence is detected by thecollating means; and inhibiting a resumption of data processing whennon-coincidence is detected by the collating means.
 21. A dataprocessing system, comprising:switch means for indicating switching onand off of a main power of said data processing system; memory means,coupled to said switch means, for storing contents of data processingperformed by said data processing system in response to an indication ofswitching off of the main power by said switch means; holding means forholding identification data; input means for inputting identificationdata; discriminating means coupled to said switch means, said holdingmeans, and said input means, said discriminating means being responsiveto said switch means, for discriminating whether identification datainput from said input means after said switch means indicates turning onof the main power coincides with the identification data held in saidholding means; executing means for, in response to detection of acoincidence in said discriminating means, resuming the data processingin accordance with a storage content of said memory means, and means forinhibiting a resumption of the data processing, to prevent contents ofthe data processing from being revealed to an unauthorized person, inresponse to detection of a non-coincidence by said discriminating means.22. A data processing system, comprising:switch means for indicatingswitching on and off of a main power of said data processing system;memory means, coupled to said switch means, for storing contents of dataprocessing performed by said data processing system in response to anindication of switching off of the main power by said switch means;holding means for holding identification data; input means for inputtingidentification data; discriminating means coupled to said switch means,said holding means, and said input means, said discriminating meansbeing responsive to said switch means, for discriminating whetheridentification data input from said input means after said switch meansindicates turning on of the main power coincides with the identificationdata held in said holding means; executing means for, in response todetection of a coincidence by said discriminating means, resuming thedata processing in accordance with a storage content of said memorymeans, and means for inhibiting a resumption of the data processing forsecurity management, in response to detection of a non-coincidence bysaid discriminating means.
 23. A data processing system,comprising:switch means for indicating switching on and off of a mainpower of said data processing system; memory means, coupled to saidswitch means, for storing contents of data processing performed by saiddata processing system in response to an indication of switching off ofthe main power by said switch means; holding means for holdingidentification data; input means for inputting identification data;discriminating means coupled to said switch means, said holding means,and said input means, said discriminating means being responsive to saidswitch means, for discriminating whether identification data input fromsaid input means after said switch means indicates turning on of themain power coincides with the identification data held in said holdingmeans; executing means for, in response to detection of a coincidence bysaid discriminating means, resuming the data processing in accordancewith a storage content of said memory means, and means for inhibiting aresumption of the data processing, to prevent an unauthorized personfrom performing the data processing, in response to detection of anon-coincidence in said discriminating means.
 24. A data processingsystem, comprising:switch means for indicating switching on and off of amain power of said data processing system; memory means, coupled to saidswitch means, for storing contents of data processing performed by saiddata processing system in response to an indication of switching off ofthe main power by said switch means; holding means for holdingidentification data; input means for inputting identification data;discriminating means coupled to said switch means, said holding means,and said input means, said discriminating means being responsive to saidswitch means, for discriminating whether identification data input fromsaid input means after said switch means indicates turning on of themain power coincides with the identification data held in said holdingmeans; executing means for, in response to detection of a coincidence insaid discriminating means, resuming the data processing in accordancewith a storage content of said memory means, and means for inhibiting aresumption of the data processing, to prevent an unauthorized personfrom interrupting the data processing, in response to detection of anon-coincidence in said discriminating means.
 25. A data processingsystem, comprising:switch means for indicating switching on and off of amain power of said data processing system; memory means, coupled to saidswitch means, for storing contents of data processing performed by saiddata processing system in response to an indication of switching off ofthe main power by said switch means; holding means for holdingidentification data; input means for inputting identification data;discriminating means coupled to said switch means, said holding means,and said input means, said discriminating means being responsive to saidswitch means, for discriminating whether identification data input fromsaid input means after said switch means indicates switching on of themain power coincides with the identification data held in said holdingmeans; executing means for, in response to detection of a coincidence insaid discriminating means, resuming the data processing in accordancewith a storage content of said memory means, and means for inhibiting aresumption of the data processing, to prevent an unauthorized personfrom performing data processing on said data processing system, inresponse to detection of a non-coincidence in said discriminating means.